CARDIAC ARREST

Cardiac arrest is the sudden loss of cardiac function, when the heart abruptly stops beating. A person whose heart has stopped will lose consciousness and stop normal breathing, and their pulse and blood pressure will be absent. Unless resuscitative efforts are begun immediately, cardiac arrest leads to death within a few minutes. This is often referred to by doctors as "sudden death" or "sudden cardiac death (SCD)."

Differentiating CARDIAC ARREST  and HEART ATTACK

Causes

Adults 

1. Cardiac diseases 
• Ischemic heart disease
• LV impairement
• Electrical abnormalities (Long QT syndrome)
• Congenital heart disease
• Valvular disease  
• Cardiomyopathy
2. Pulmonary embolism
3. Aortic dissection
4. Gastrointestinal hemorrhage
5. Respiratory failure
6. Metabolic disturbance (e.g. drug overdose)

Children 

1. Poisoning
2. Diseases of the respiratory system
3. Trauma

Investigations

1. Cardiac biomarkers (troponin and CK-MB)
2. Serum electrolytes (severe alterations can increse risk of arrythmias)
3. Drug levels above the normal therapeutic values may increase arrythmic effect (e.g. TCAs, quinidine and digoxin)
4. Toxic screening (for toxins that can induce vasospasmic ischemia)
5. Brain natriuretic peptide (BNP)
6. ECG monitoring
7. Coronary angiography (help determine patients who can benefit from revascularisation procedures)
8. TSH (hyperthyroidism can lead to tachycardia)

MANAGEMENT

1.      Remove any possible danger to the patient.

2.      Check whether the client is responsive. Ideally for this the clients shoulders should be held and shake to see the response. Or else can compress xiphoid process to see whether the client is responsive.

3.      If outside the hospital call the ambulance. If within the hospital inform the cardiac arrest team or the relevant professionals.

4.      Then asses the airway. Check for patency and any obstruction. If there is any obstruction remove.

5.      Then asses breathing. Generally ones in cardiac arrest will show no breathing or will be extremely low. For clients who are not responsive and who are responsive but with abnormal breathing CPR should be given.

6.      If it is outside the hospital and an automated external defibrillator is available deliver one shock as instructed by the device and then start CPR.

7.      Start chest compressions with placing the heel of one hand on the chest of the patient and the other covering it. Keep the elbows straight and compress with the upper body weight at a rate of 100 compressions a minute.

8.      If outside the hospital, do 30 compressions at the above mentioned rate and tilt the head to open the airway and asses the breathing for 10 seconds. If no breathing, give 2 rescue breaths and repeat chest compressions. This cycle, 30 compressions and 2 rescue breaths, should be continued until the patient is taken to the hospital. If within the hospital chest compressions are done continuously as an ambu bag can be used to give rescue breaths continuously with assistance.

9.      CPR should be continued until the victim recovers or the medical emergency personnel take over.

At the emergency department the client should be stabilized, assessed and treated for the cause. Sometimes the clients will require intubation. Usually defibrillation is done right after by giving shocks to get back the heart rhythm normal. Treatments may include antiarrhythmic drugs, implantable cardioverter defibrillation, angioplasty or a CABG depending on the cause.  

 References

• American Heart Association 2014, 'About Cardiac Arrest', retrieved 26 April 2015, <http://www.heart.org/HEARTORG/Conditions/More/CardiacArrest/About-Cardiac-Arrest_UCM_307905_Article.jsp>
• Mayo clinic 2015, ' Sudden cardiac arrest', retrieved 26 April 2015, <http://www.mayoclinic.org/diseases-conditions/sudden-cardiac-arrest/basics/symptoms/con-20042982>
• O'Connor, R.E. 2015, 'Cardiac arrest', retrieved 26 April 2015, <http://www.merckmanuals.com/professional/critical-care-medicine/cardiac-arrest/cardiac-arrest>
• Sovari, A.A. 2014, 'Sudden Cardiac Death', retrieved 26 April 2015, <http://emedicine.medscape.com/article/151907-overview#aw2aab6b2b2aa>
• Jameson, J. N. St C.; Dennis L. Kasper; Harrison, Tinsley Randolph; Braunwald, Eugene; Fauci, Anthony S.; Hauser, Stephen L; Longo, Dan L. (2005). Harrison's principles of internal medicine. New York: McGraw-Hill Medical Publishing Division.